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Vladimir Lukyanov's hydraulic computer

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Re: Vladimir Lukyanov's hydraulic computer

#71

Post by gumby »

nestorD wrote: post #35
bno1 wrote: post #34

Earlier quoted context omitted.

If they had a plot of the function in a digital format that could be printed what stopped them from doing numerical integration?

It was not invented yet, the "Mathematical Model for the Determination of Total Area Under Glucose Tolerance and Other Metabolic Curves" paper came out in 1994... https://fliptomato.wordpress.com/2007/03/19/medical-research...

When I was learning to use a chromatograph (barely a decade ago) the textbook still suggested the "plate stacking method" to figure out the AUC (area under the curve): basically see how many rectangles fit under the curve.

Re: Vladimir Lukyanov's hydraulic computer

#72

Post by [deleted] »

ams6110 wrote: post #70
tomxor wrote: post #56

Earlier quoted context omitted.

> 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 techni…

[deleted]

Re: Vladimir Lukyanov's hydraulic computer

#73

Post by yesenadam »

nestorD wrote: post #35
bno1 wrote: post #34

Earlier quoted context omitted.

If they had a plot of the function in a digital format that could be printed what stopped them from doing numerical integration?

It was not invented yet, the "Mathematical Model for the Determination of Total Area Under Glucose Tolerance and Other Metabolic Curves" paper came out in 1994... https://fliptomato.wordpress.com/2007/03/19/medical-research...

Original paper, which appeared in Diabetes Care.

https://math.berkeley.edu/~ehallman/math1B/TaisMethod.pdf

Reading it, it's quite hard to believe it wasn't a joke, but it doesn't seem to be. It thanks R. Kuc of Yale (a professor of electrical engineering) for his expert review.

Google Scholar says it has 336 citations, most of which appear to be non-ironic[0].

The original paper was immediately followed (i.e. in the same issue) by two corrective articles[1], one titled "Tai's Formula Is the Trapezoidal Rule". So why did they publish it at all? This page discusses that question:

https://academia.stackexchange.com/questions/9602/rediscover...

..and links to this, which talks about how wheels are reinvented all the time.

https://academia.stackexchange.com/questions/7360/how-common...

[0] http://scholar.google.com/scholar?cites=18129095207210817294...

[1] http://libgen.io/scimag/ads.php?doi=10.2337%2Fdiacare.17.10....

Re: Vladimir Lukyanov's hydraulic computer

#74

Post by disposablename »

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…

Trickle-down economics

Re: Vladimir Lukyanov's hydraulic computer

#75

Post by yesenadam »

I'm not sure how different this is to the ball integrator?[0] or Vannevar Bush's differential analyser?[1] The water computer article says partial differentiator, then integrator, it's unclear.

[0] https://en.wikipedia.org/wiki/Ball-and-disk_integrator

[1] https://en.wikipedia.org/wiki/Differential_analyser

Re: Vladimir Lukyanov's hydraulic computer

#76

Post by [deleted] »

nestorD wrote: post #35
bno1 wrote: post #34

Earlier quoted context omitted.

If they had a plot of the function in a digital format that could be printed what stopped them from doing numerical integration?

It was not invented yet, the "Mathematical Model for the Determination of Total Area Under Glucose Tolerance and Other Metabolic Curves" paper came out in 1994... https://fliptomato.wordpress.com/2007/03/19/medical-research...

[deleted]

Re: Vladimir Lukyanov's hydraulic computer

#77

Post by SmellyGeekBoy »

DonHopkins wrote: post #58
B1FF_PSUVM wrote: post #26

Earlier quoted context omitted.

Incidentally, these were the computers in the early Heinlein books. I was mulling the comment here a few days ago pointing out Heinlein's prescient depiction of networked computers, and thinking that the hard part would be having mechanical computers pick up the phone and sending electromagnetic pulses down the line. Perhaps pecking at telegraph keys ...

Ash the Android in Alien used a water based computer. Or maybe that was milk. It looks like he might have been had problems solving non-homogeneous differential equations, because the cream would rise to the top. https://www.youtube.com/watch?v=VA8jv1M6Y2g

I always thought it was some kind of hydraulic fluid but I prefer your explanation. ;)

Re: Vladimir Lukyanov's hydraulic computer

#78

Post by SmellyGeekBoy »

whatshisface wrote: post #62
DonHopkins wrote: post #59

Earlier quoted context omitted.

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.

Gives a whole new meaning to the term "wiretap".
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