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Re:The perfect shape by colanderman on Friday May 16, 2014 @11:59PM (#7759185)
Oh, I've heard this one before. Then the physicist fills a balloon with water and sticks a straw in it, proclaiming it a dynamically optimal system (in the absence of gravity); and finally the engineer sprays foam insulation on a glass jar and calls it a day.
Re:The perfect shape by getbreadbox on Saturday May 17, 2014 @11:56AM (#7760474)
Yeah, these double walled cups work quite well:

http://www.amazon.com/gp/aw/d/B004NBXR98/ref=mp_s_a_1_1?qid=...

Re:The perfect shape by jey on Friday May 16, 2014 @10:45PM (#7759082)
Awesome, but why a genetic algorithm? I wonder if it could be formulated as a tractable optimization problem instead.
Re:The perfect shape by gravity13 on Friday May 16, 2014 @11:49PM (#7759172)
Or perhaps solved more purely using Calculus of Variations.
Re:The perfect shape by joaquintides on Saturday May 17, 2014 @11:02AM (#7760308)
I've added a small postscript explaining why calculus of variations (in its simplest form at least) is not applicable to this problem.
Re:The perfect shape by foxlisk on Saturday May 17, 2014 @01:06AM (#7759282)
that was my first thought too. we developers sometimes get so caught up in development weforget there's a whole world of other tools.
Re:The perfect shape by elteto on Friday May 16, 2014 @11:07PM (#7759124)
I was thinking the same thing. It is a good exercise to test a genetic algorithm but a numerical solver could have been used as well.
Re:The perfect shape by colordrops on Saturday May 17, 2014 @01:25AM (#7759301)
Interesting, this shape matches exactly the yogurt jars sold on the streets in Beijing. They need to remain cool without refrigeration for long periods of time.
Re:The perfect shape by jameshart on Saturday May 17, 2014 @09:21AM (#7760040)
Then they should be spherical; this shape's optimal only for a container which is gradually emptying.
Re:The perfect shape by dpiers on Saturday May 17, 2014 @12:27PM (#7760562)
A liquid container designed to keep its contents cool as long as possible? Sounds like a the job for a dewar flask. I've left drinks out in this overnight and they were still cold in the morning:

https://shop.funraniumlabs.com/products/665ml-fmj-textured-v...

Re:The perfect shape by natch on Saturday May 17, 2014 @01:05AM (#7759280)
Perfect all depends on what you're optimizing for.

If you want a glass that doesn't tip over easily, this isn't so great.

Theory versus practice. The best entrepreneurs are able to see past the theory and grapple with practical considerations.

Re:The perfect shape by jameshart on Saturday May 17, 2014 @09:22AM (#7760041)
Take this shape, minimize thermal conductivity to its surroundings but enable it to stand safely on a flat surface, and what you have got is a stemmed wine glass.
Re:The perfect shape by twic on Saturday May 17, 2014 @08:22AM (#7759940)
Re:The perfect shape by dj-wonk on Friday May 16, 2014 @08:02PM (#7758657)
I may be reading this wrong, but I think this means that a shot glass is mathematically perfect.
Re:The perfect shape by nkozyra on Friday May 16, 2014 @09:55PM (#7758965)
I can only read this wrong because I found a shot glass "mathematically perfect" earlier this evening.
Re:The perfect shape by nine_k on Saturday May 17, 2014 @12:52AM (#7759263)
I'd notice that this must also describe the best shape of a glass to keep a beverage hot. But, unlike shot glasses, tea and coffee cups look very different.
Re:The perfect shape by joaquintides on Saturday May 17, 2014 @11:11AM (#7760337)
As you correctly point out the problem is entirely symmetrical to that of keeping a hot beverage as hot as possible. If we take the different problem of trying to cool a hot beverage, the optimum, pathological solution would be a glass with 0 height and infinite width --studying this problem with the additional constraint that width be limited to some predefined value might make for an interesting followup article.
Re:The perfect shape by Someone on Saturday May 17, 2014 @12:09PM (#7760513)
I would add the constraint that the surface is convex, too. Without that, one could build some 3D fractal, and get infinite area for any given volume.

Alternatively, complicate things by taking the width of the glass into account or model convection more realistically (a square meter of glass close to other glass of similar temperature will not lose much heat)

Re:The perfect shape by maho on Saturday May 17, 2014 @09:00AM (#7760001)
I guess that the ratio h_open/h_closed is much bigger for hot beverages, due to evaporative cooling. Of course, this would mean that the optimum shape is even thinner than those that were calculated.

But maybe the shape of tee-cups and coffee mugs is optimal, in its own way? I certainly appreciate that beverages that need quite high temperatures for brewing are cooled down quickly to a drinkable temperature.

Re:The perfect shape by dj-wonk on Saturday May 17, 2014 @11:02PM (#7761997)
I think shot glasses are optimized to be put into various configurations, such as matrices and triangular matrices: http://www.likecool.com/Home/Accessories/Billiards%20Shot%20...
Re:The perfect shape by Mathnerd314 on Friday May 16, 2014 @11:21PM (#7759143)
So when is the kickstarter?