Wonder if they had cross-core security vulnerabilities?
You'd have to worry about information leakage.
Vladimir Lukyanov's hydraulic computer
51–60 of 78 posts
Re: Vladimir Lukyanov's hydraulic computer
#52> he water level in various chambers (with precision to fractions of a millimeter) represented stored numbers I wonder how did they deal with thermal expansion. Maybe instead of using water at room temp they heated it to something higher and then a thermostat took care of it? But it still would be very hard to distribute heat evenly.
Thermodynamics lab tech was pretty advanced by that time.
The part that reads bogus to me is the fractions of a mm, water meniscus is sensitive to contamination and diameter, its "always" been easier to measure liquid masses to higher sig figs than to measure liquid volumes, I suspect the journalist filter turned mg into mm or the precision scale produced repeatable results equivalent to fractions of a mm in the container. The only solution I can come up with that would work in that era would be something weirdly optical involving mirrors and multiple floats.
I vaguely remember a quarter century ago in a chemistry lab placing a beaker of distilled room temp water in a very nice precision scale as a demonstration while the instructor had us calculate how long it would take the inch or so of water to evaporate based on the slowly decreasing mass, and the result during a dry winter was somewhere around a month. The room must have been sealed and 100% humidity because small fractions of a mm in height would represent in a very hand wavy way around a minute of evaporation if represented as time in normal winter lab air. I also wonder how volume of water changes as CO2 is absorbed or emitted by the water, even the smallest gas bubble could mess up fraction of a mm measurements.
Re: Vladimir Lukyanov's hydraulic computer
#53Earlier 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?
The user interface of scissors and scale is much faster than the human/computer user interface for numerical integration after fitting a smoothed curve to the measured data. The human scissor operator, in theory, can exercise far better judgment at throwing out invalid data points than an algorithm, when fitting curves. (When I was measuring datapoint 15 I know I was distracted, no surprise its an outlier, I can safe…
I think the concomitant risk is that a human scissor operator can also apply bias, sometimes unconsciously.
Re: Vladimir Lukyanov's hydraulic computer
#54The real deal and the future is here. You should contact a reliable and professional private investigator for all sort of hacking, spying and data retrieval services. Contact lucidionysus at gmail.com today and thank me later.
Re: Vladimir Lukyanov's hydraulic computer
#55In 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.
This reminds me of how the geographical center of the US was once found by balancing a cardboard cutout [1]; an accompanying document then explains the limitations and caveats of this method and of other methods which produce different results, while musing about the discrepancy between the ambiguity of the ask and the public's expectations of producing a clear and reproducible answer.
[1] (PDF) https://www.ngs.noaa.gov/PUBS_LIB/GeoCenter_USA1.pdf
Re: Vladimir Lukyanov's hydraulic computer
#56Earlier quoted context omitted.
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...
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 recently: implementing a very simple little tool to integrate raw data, (I don't know calculus well at all) but here is my thought process (and probably most peoples):
1. I just want basic integration of raw data, something simple no interpolation at this stage.
2. hmm just draw a polyline through the points - how do I find the area it outlines (figure that bit out quickly it's just basic trig then some simplification, all very intuitive).
3. Ok that's how I find the area, I wonder what this is called it's too simple to not have been discovered hundreds of years ago... goes and does some searching to find matching definition.
... What kind of person gets to step 3 and marvels at their re-invention of the trapezoidal rule and goes straight to publishing a paper? How is it they are "doing science"?
Re: Vladimir Lukyanov's hydraulic computer
#57[deleted]
Re: Vladimir Lukyanov's hydraulic computer
#58In a related vein, Ars Technica writer Sean Gallagher did a fantastic story on the US Navy's analog fire guidance computers a few years ago: https://arstechnica.com/information-technology/2014/03/gears... The instruction videos alone are worth the visit. Geekery of the first order.
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.
Re: Vladimir Lukyanov's hydraulic computer
#59Earlier quoted context omitted.
Even better, is remote hacking of analog computer even possible?
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?
Re: Vladimir Lukyanov's hydraulic computer
#60If you squinted, you might consider the U.S. Army Corps of Engineers Bay Model a giant low tech special purpose water computer.
https://en.wikipedia.org/wiki/U.S._Army_Corps_of_Engineers_B...
>The U.S. Army Corps of Engineers Bay Model is a working hydraulic scale model of the San Francisco Bay and Sacramento-San Joaquin River Delta System. While the Bay Model is still operational, it is no longer used for scientific research but is instead open to the public alongside educational exhibits about Bay hydrology. The model is located in the Bay Model Visitor Center at 2100 Bridgeway Blvd. in Sausalito, California.