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>> What, as opposed to "what is the unladen velocity of a swallow?"? 0;-)
>
> I'd say about 30mph because when driving at that speed sometimes birds
> appear to be going about the same speed :-)
Heh. I don't think you can try that on horseback. (Although after
several months I have yet to discover what the typical speed of a horse
actually is.)
> Estimate the mass of air in this room.
3 grams?
> Would birds be hotter or colder with fur on their legs?
Presumably this varies depending on the external temperature?
> Draw x^infinity + y^infinity = 1.
__ __ __ __
|__|__| |__|__|
\ / | \ / /|
\ / | \ / -------- |
\/ ---+--- \/ |
/\ | / -------- |
/ \ | / |
/ \ / --+--
...oh, wait, maybe you meant the *graph* of this?
> Prove which is bigger, e^pi or pi^e
Hmm. Well two cubed is 8, while three squared is 9, so I'm going to go
with pi^e being larger. Presumably "proving" this would simply involve
slightly more arithmetic. :-P
> But the best one was at my university interview, the guy had given me
> some quite tricky geometry/trig problem to solve and I think I almost
> had the answer, but the equation was a huge mess and I was dreading to
> try and solve it for x (or whatever, it had squares and cubes all over
> the place). But then at that point he says "great, you seem to have the
> answer if you just tidy it up a bit, let's move on". Was the best I
> could have hoped for!
Heh, neat.
I remember spending about a week trying to figure out how Euler's
relation allows me to compute the complex exponent of a complex
quantity. I don't know why it took me so long; it's really quite simple
when you look at it. I think I just confused myself too much to see it...
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On 20-2-2009 15:18, Invisible wrote:
> Anyway, as to what percentage of the population understand the Fourier
> Transform, I wouldn't like to say.
In my experience very little. Which does not stop them from using it
when a package provides it.
Proposition #6 from my thesis: the use of FFT to extract clinically
relevant parameters should be forbidden in the field of cardiology.
> I don't meet many people... I'm sure
> in any kind of competetive process though, you're going to meet a hell
> of a lot of them.
Then why do have to import our PhD students? After Dutch and English,
Russian is now the third language in our lab. Two years ago it was Italian.
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>> Anyway, as to what percentage of the population understand the Fourier
>> Transform, I wouldn't like to say.
>
> In my experience very little. Which does not stop them from using it
> when a package provides it.
> Proposition #6 from my thesis: the use of FFT to extract clinically
> relevant parameters should be forbidden in the field of cardiology.
Uh... I was under the impression that most of the useful information in
a cardiagram is in the time-domain anyway...? (OTOH, IANAD.)
>> I don't meet many people... I'm sure in any kind of competetive
>> process though, you're going to meet a hell of a lot of them.
>
> Then why do have to import our PhD students? After Dutch and English,
> Russian is now the third language in our lab. Two years ago it was Italian.
No idea.
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On 20-2-2009 15:51, Invisible wrote:
>>> Anyway, as to what percentage of the population understand the
>>> Fourier Transform, I wouldn't like to say.
>>
>> In my experience very little. Which does not stop them from using it
>> when a package provides it.
>> Proposition #6 from my thesis: the use of FFT to extract clinically
>> relevant parameters should be forbidden in the field of cardiology.
>
> Uh... I was under the impression that most of the useful information in
> a cardiagram is in the time-domain anyway...?
Spot on.
I once saw this procedure to find a phenomenon that occurs every other
beat.: Find the time instant in every beat where you expect the change.
Create a time series of that. Do an FFT. look at the amplitude of the
center frequency. Ok, I admit it works and you can include a spectrum in
your paper...
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Invisible wrote:
> I actually have no idea what you're talking about - although spending 3
> years evaluating the intelligence of a half-mouldy cup of yogurt does
> seem like an amusing prospect. ;-)
That could be your dissertation. :-D
--
~Mike
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andrel wrote:
> John had some problems with below average IQ and EQ people when he was
> teaching, that is why he isn't anymore.
My wife is a teacher (elementary students) I seriously don't understand
how she keeps from going homicidal. She's a very patient person.
--
~Mike
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>>> Proposition #6 from my thesis: the use of FFT to extract clinically
>>> relevant parameters should be forbidden in the field of cardiology.
>>
>> Uh... I was under the impression that most of the useful information
>> in a cardiagram is in the time-domain anyway...?
>
> Spot on.
Uh... so you're telling me I know more about cardiagrams than the people
attempting to interpret them? o_O
> I once saw this procedure to find a phenomenon that occurs every other
> beat.: Find the time instant in every beat where you expect the change.
> Create a time series of that. Do an FFT. look at the amplitude of the
> center frequency. Ok, I admit it works and you can include a spectrum in
> your paper...
I have a vague recollection that somebody designed an ANN that worked on
ECG data in the frequency domain and was reputedly quite accurate. OTOH,
the details were sparse. (It was an introductory text on ANNs, basically
it had a section on "hey, look how useful these are! You should learn
about them.")
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> My wife is a teacher (elementary students) I seriously don't understand
> how she keeps from going homicidal. She's a very patient person.
...so she teaches Boron and Lithium who to do their ABCs?
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>> I actually have no idea what you're talking about - although spending
>> 3 years evaluating the intelligence of a half-mouldy cup of yogurt
>> does seem like an amusing prospect. ;-)
>
> That could be your dissertation. :-D
...and now I'm thinking about the "Ode to a lump of putty I found in my
left armpit". :-S
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>> Estimate the mass of air in this room.
>
> 3 grams?
Estimate, not guess! You'll never make an Engineer if you can't tell when
your calculations are off by several orders of magnitude. BTW a cubic metre
of air is about 1kg, so you must be in a very small room.
>> Would birds be hotter or colder with fur on their legs?
>
> Presumably this varies depending on the external temperature?
I think it's safe to assume the external temperature is lower than the
internals of the bird, but anyway the point of this one was that for
cylinders below a certain radius lagging them actually makes them release
more heat rather than less, because the surface area increase has more
affect than the lagging. Useful to know if you ever think about insulating
thin pipes :-)
> ...oh, wait, maybe you meant the *graph* of this?
Har har.
> Hmm. Well two cubed is 8, while three squared is 9, so I'm going to go
> with pi^e being larger.
Wrong!
> Presumably "proving" this would simply involve slightly more arithmetic.
> :-P
http://mathforum.org/library/drmath/view/53916.html
> quantity. I don't know why it took me so long; it's really quite simple
> when you look at it. I think I just confused myself too much to see it...
That was the story of my whole thermodynamics course at university!
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