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Vladimir Lukyanov's hydraulic computer

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Re: Vladimir Lukyanov's hydraulic computer

#61

Post by wpietri »

I know of two excellent examples of this. One is an entertaining modern attempt to recreate economic models with a fluid computer: https://vimeo.com/131690448

The other is the fucking fantastic Bay Model, a 1:1000 physical model of the San Francisco Bay: https://en.wikipedia.org/wiki/U.S._Army_Corps_of_Engineers_B...

It was built in the 1950s to study the effects of various plans, including one proposal to divert all incoming rivers to "productive" use. It was eventually made obsolete by computer simulation, but it's still there. I bring a lot of my nerdy out-of-town visitors there; it's amazing to walk around on a 2-acre simulation.

Re: Vladimir Lukyanov's hydraulic computer

#62

Post by whatshisface »

DonHopkins wrote: post #59
whatshisface wrote: post #46

Earlier quoted context omitted.

It's not connected to anything, so probably not. However back when we used purpose-built electromechanical switching systems for telephones, people exploited them[0]. [0] https://en.m.wikipedia.org/wiki/Phreaking

If the phone system used water instead of electricity for in-band signaling, would phone phreaks have to inject blue fluid into the pipes to exploit them?

If water pipes were used for signalling, it would probably be as acoustic conduits (analogous to wires, which are electromagnetic wave conduits). You would exploit them in just about the same way as the electromechanical systems were.

Re: Vladimir Lukyanov's hydraulic computer

#63

Post by JKCalhoun »

wpietri wrote: post #61

I know of two excellent examples of this. One is an entertaining modern attempt to recreate economic models with a fluid computer: https://vimeo.com/131690448 The other is the fucking fantastic Bay Model, a 1:1000 physical model of the San Francisco Bay: https://en.wikipedia.org/wiki/U.S._Army_Corps_of_Engineers_B... It was built in the 1950s to study the effects of various plans, including one proposal to divert all…

Yes, first link is based on the MONIAC: https://en.wikipedia.org/wiki/MONIAC

Re: Vladimir Lukyanov's hydraulic computer

#64

Post by JKCalhoun »

jedimastert wrote: post #29
bencollier49 wrote: post #27

This rather reminds me of the economic model in Terry Pratchett's "Making Money".

Fun fact, the device you're referring to was actually based on a different real-life water-based computer, the MONIAC[1]. It used basins of water, pipes, and adjustable flow regulators as a physical metaphor for the movement of money in macro-economics. I'm personally a really big fan, and I've need meaning to work up a simulation for quite some time now. [1]: https://en.wikipedia.org/wiki/MONIAC

Awesome. I imagine a Water Computer Construction Set that allows you to "plumb" a computer program.

Re: Vladimir Lukyanov's hydraulic computer

#65

Post by JKCalhoun »

agumonkey wrote: post #14

Similarly there was a story about a ~computer based on water surface tension to encode complex equations and let the physics approximate a solution in parallel. Can't find the name though.

Found an online link to one of the articles Dewdney wrote for Scientific American about "analog computers" (this is the second article, there was one a year earlier):

http://www.softouch.on.ca/kb/data/Scan-130202-0003.pdf

Re: Vladimir Lukyanov's hydraulic computer

#66

Post by jaclaz »

toolslive wrote: post #15

In the 1980s people in chemistry labs that needed to find the area beneath a curve used to print/plot the curve, cut out the area and weigh it. This worked quite well as they had accurate scales.

More generally, there was a dedicated instrument to calculate areas of a map or drawing, the planimeter, widely used before the advent of (affordable) computing:

https://en.wikipedia.org/wiki/Planimeter

https://news.ycombinator.com/item?id=16032930

Re: Vladimir Lukyanov's hydraulic computer

#70

Post by ams6110 »

tomxor wrote: post #56
konschubert wrote: post #38

Earlier quoted context omitted.

I hope that's a joke. The most basic numeric integration method is so simple I don't think it needed to be invented.

> The most basic numeric integration method is so simple I don't think it needed to be invented. Exactly, the individual who came up with that paper shows a complete lack of imagination, not merely ignorance - how someone (scientist or not) lacks the ability to see the likelihood of such a simple method having been discovered before is quite puzzling to me... This happens to be closely related to what I was doing rec…

And how is it that the paper got reviewed and accepted for publication without somebody pointing out the obvious?

As a 1980s high school student my first thought of how I'd find the area under a curve with a computer was basically to pick random points and see if they were above or below the curve. At the time I had about one year of exposure to Apple II basic. My math teacher said "yeah that's the Monte Carlo technique."

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