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[jim hardy]

Surface integrals are a work of evil.

I remember greatly enjoying them on straightforward surfaces like a sphere. Then you hit real world where nothing quite fits those nice textbook examples. Aaarghhh !

A volume integral for a vertical cylindrical tank with elliptical top and bottom once drove me bananas..
Biggest problem was arctan function blew up at some particular value
so i wrote a Taylor series expansion for it
All i had was a TI-99 with interpreted Basic , it was really fun to watch it think as it iterated in on solutions near the cusp.
But i got an "Attaboy" for producing the calibration curve of gallons versus height. We made a special scale for the meter to accommodate the nonlinearity.

old jim

 

[WWGD]

Personally, I am not sure what a terrier looks like, so a picture definitely helps. I don't know the names of too many dog styles. I know pit bulls because I think they have alligator faces. Dalmations have spots. German shepherds have that dangerous wolfy edge. The Irish wolf hound is really big. The golden retriever is blond and friendly. That's about it. Well, the chiuhahua. However you spell it. Sometimes I've seen a certain kind of dog and wondered if it might be a rotweiller. St. Bernard, of course. That's about it. Well, the husky. Cats are easier, there's only three styles: normal, siamese, and smash-faced. Well, there's long haired and short haired and bald, I guess.

Yes, I just suggest

I remember greatly enjoying them on straightforward surfaces like a sphere. Then you hit real world where nothing quite fits those nice textbook examples. Aaarghhh !

A volume integral for a vertical cylindrical tank with elliptical top and bottom once drove me bananas..
Biggest problem was arctan function blew up at some particular value
so i wrote a Taylor series expansion for it
All i had was a TI-99 with interpreted Basic , it was really fun to watch it think as it iterated in on solutions near the cusp.
But i got an "Attaboy" for producing the calibration curve of gallons versus height. We made a special scale for the meter to accommodate the nonlinearity.

old jim

Well done, Sir, real-life Mathematics/Engineering.

 

[Ibix]

But i got an "Attaboy" for producing the calibration curve of gallons versus height. We made a special scale for the meter to accommodate the nonlinearity.

Out of interest, why not dump water in the top gallon by gallon and mark the level?

 

[WWGD]

Out of interest, why not dump water in the top gallon by gallon and mark the level?

Good idea, or, by ( I assume) symmetry, fill it approx halfway and double the total.

 

[fresh_42]

Good idea, or, by ( I assume) symmetry, fill it approx halfway and double the total.

Or simply fill only the right half, so one can put the ruler inside and mark it more accurately.

 

[WWGD]

Or simply fill only the right half, so one can put the ruler inside and mark it more accurately.

How do you fill just the right half without water poring through?

 

[Borg]

How do you fill just the right half without water poring through?

Fill the left half first of course.

 

[Ibix]

Fill the left half first of course.

...being careful not to overfill it. You wouldn't want to double-fill the overlap.

 

[WWGD]

Fill the left half first of course.

Or the center one, leaving the bottom and top quarters empty. It reminds me of designated quiet areas in some libraries that are right next to ones where speaking is allowed ( and a -loud too ;) ) as if sound will follow orders and stop beyond the speaking-allowed areas.

 

[OCR]

...dump water in the top gallon by gallon and mark the level?

...fill it approx halfway and double the total.

Wasn't that what Michio Kaku was doing ??

...figure skating.

 

[WWGD]

Wasn't that what Michio Kaku was doing ??

In a very abstract way, yes ;).

 

[jim hardy]

Out of interest, why not dump water in the top gallon by gallon and mark the level?

It was about a twelve thousand gallon tank. In a radioactive location. And in a nuke plant everything has to be backed by an engineering calculation.
Initially we only used the cylindrical mid-part of the tank, with level instrument taps located at the joints between cylindrical midsection and elliptical top/bottom. So "Empty" indication was really a foot or so above the actual bottom and "Full" similarly about a foot below the actual top.
Engineering decided we needed a little more useable tank capacity so rather than buy a bigger tank they sent in the welders to move the level measuring taps to very tip-top and bottom of tank, adding a couple feet of measurable height. But those extra two feet being in curved sections of the tank had nonlinear gallons versus %level. And we wanted readout for the operators in gallons not % level.

Somehow it fell to me, a lowly instrument maintenance guy, to produce the calculation to make the inventory meter read correct number of gallons. . It was actually quite fun.

 

[Ibix]

twelve thousand gallon tank. In a radioactive location. And in a nuke plant everything has to be backed by an engineering calculation.

Three excellent reasons...

 

[WWGD]

It was about a twelve thousand gallon tank. In a radioactive location. And in a nuke plant everything has to be backed by an engineering calculation.
Initially we only used the cylindrical mid-part of the tank, with level instrument taps located at the joints between cylindrical midsection and elliptical top/bottom. So "Empty" indication was really a foot or so above the actual bottom and "Full" similarly about a foot below the actual top.
Engineering decided we needed a little more useable tank capacity so rather than buy a bigger tank they sent in the welders to move the level measuring taps to very tip-top and bottom of tank, adding a couple feet of measurable height. But those extra two feet being in curved sections of the tank had nonlinear gallons versus %level. And we wanted readout for the operators in gallons not % level.

Somehow it fell to me, a lowly instrument maintenance guy, to produce the calculation to make the inventory meter read correct number of gallons. . It was actually quite fun.

No " Homer-Simpsoning" allowed ?

 

[WWGD]

Windows recommends, for internet connectivity problems to...contact Customer Support Online". They also switched from the error message " Windows has encountered a problem and will be shutting down to " . " Your PC has encountered a problem and will be shutting down.

 

[jim hardy]

No " Homer-Simpsoning" allowed ?

Homer was quite a bit higher in the company than I .

 

[zoobyshoe]

It was about a twelve thousand gallon tank. In a radioactive location. And in a nuke plant everything has to be backed by an engineering calculation.
Initially we only used the cylindrical mid-part of the tank, with level instrument taps located at the joints between cylindrical midsection and elliptical top/bottom. So "Empty" indication was really a foot or so above the actual bottom and "Full" similarly about a foot below the actual top.
Engineering decided we needed a little more useable tank capacity so rather than buy a bigger tank they sent in the welders to move the level measuring taps to very tip-top and bottom of tank, adding a couple feet of measurable height. But those extra two feet being in curved sections of the tank had nonlinear gallons versus %level. And we wanted readout for the operators in gallons not % level.

Somehow it fell to me, a lowly instrument maintenance guy, to produce the calculation to make the inventory meter read correct number of gallons. . It was actually quite fun.

I'm wondering: why the odd shape for the tank?

 

[dlgoff]

I'm wondering: why the odd shape for the tank?

I have no doubt it was ordered by a bean counter considering volume not shape. Those guys do help make engineers lives interesting though.

 

[jim hardy]

I'm wondering: why the odd shape for the tank?

Actually it's fairly common the have elliptical ends on a tank.

http://www.bakertankhead.com/products/tank-heads.htm

but we usually measure level in inches or % of tank height, not thinking so much of actual gallons of inventory as " are we approaching empty and about to uncover a pump suction ,
or are we about to overflow?"
Former ingests air, latter makes a mess of a room.

Some new "What if" analysis said the tank needed to be just a little bit bigger than what had been ordered and installed twenty years before.. Including the volume of its top and bottom satisfied the analysis.

old jim

 

[zoobyshoe]

Actually it's fairly common the have elliptical ends on a tank.

Oh! Now that I see the pictures, it's clear. I was envisioning the ellipse being on a different axis, like if you took a paper towel tube and squeezed the ends.

 

[OCR]

In a very abstract way, yes ;).

Yeah, I thought maybe dkotschessaa was making a pun... he's an abstract guy, after all...lol

 

[dkotschessaa]

Yeah, I thought maybe dkotschessaa was making a pun... he's an abstract guy, after all...lol

Nope. This was real.

 

[Borek]

OK, I know it is behind a paywall and in Polish, so you won't be able to neither read it nor understand, still, being interviewed by one of the most influential papers in Poland (and one of the most hated ones, mostly for promoting this liberal democracy thing) is something I am ready to boast about.

http://wyborcza.pl/duzyformat/7,127...rozmowa-z-marcinem-borkowskim-redaktorem.html

(it is mostly about early computer press in Poland and magazines I worked for - "Bajtek" and "Top Secret")

 

[dlgoff]

... is something I am ready to boast about.

And you should. Congratulations @Borek. This is how the article's title translated using Google Translate:

What killed "Byte"? Conversation with Marcin Borkowski, editor of the first cult computer magazine

How cool is that.

Now I have a "current photo" of you in My Documents\Physicsforums\Borek folder. That makes seven all together. One from the PF photo contest, Brown, where you are very,very tan without your shirt. An image with two photos of you and your brother. One showing just your black and blue swollen ankle. One where, to me, you look like a secret service agent; you're wearing a cap and sunglasses and have a very serious expression. One Facebook photo. And one that I think you wife posted when you were very young working on something inside your house in just you underwear.

Should I post them in the PF Member Phot0s Part 2?

Runs and Hides before getting banned.

 

[Borek]

The one with my real brother, or the trick one?

FB photo? Have you seen Junior, my half brother and me?

 

[dlgoff]

The one with my real brother, or the trick one?

FB photo? Have you seen Junior, my half brother and me?

Hoping not to be banned, I'll have to upload them for you to see. Let me know if I was mistaken.

You and your brother

FB 1

FB 2

 

[Borek]

The one "with my brother" is a trick shot (on a film, with a technique dated to pre-Photoshop times). But I have real half brother (on the right), just a year older than Junior:

 

[zoobyshoe]

The T-shirts are all in English.

 

[dlgoff]

The one "with my brother" is a trick shot (on a film, with a technique dated to pre-Photoshop times). But I have real half brother (on the right), just a year older than Junior:

View attachment 204208

Well alright then. I'll change my documentation on the "Trick Brother" photo and add this good "all together" photo. Thanks for clarifying.

 

[Borek]

The T-shirts are all in English.

Funny, isn't it? Caught my attention as well.