kens

58 ms·

481.
by kens 2y ago
I don't think anyone has mentioned the context of the Hacker Purity Test. Back in the 80s, the "Purity Test" was a well-known thing on Usenet, a long list of sexual activities, drugs, and so forth. By checking off which thing
482.
by kens 2y ago
The article says that Robinhood has "an undisclosed $10 fee on every $100 investment." That seems absurdly high. But is it true? I did a minute of research and couldn't find any fees like that.
483.
by kens 2y ago
That reminds me of the 2007 incident when the Air Force meant to transfer twelve unarmed cruise missiles from North Dakota to Louisiana but loaded up six nuclear-tipped missiles by mistake. The missiles remained unprotected on a B-52 for 36
484.
by kens 2y ago
I haven't looked at submarine systems in detail, but my understanding is that the big problem is that an ICBM knows where it's starting, but the submarine travels. So submarines have super-accurate inertial navigation systems on b
485.
by kens 2y ago
There are two factors. First, any missile with inertial guidance needs to have a precise angle reference as a basis for the guidance system. If the guidance system starts off slightly wrong about which way is North, it's going to miss
486.
by kens 2y ago
One can't cancel out random errors by integrating. You should take kragen's suggestion and write a quick simulation. To make this concrete, flip a coin 10 times. Take a step to the left for heads and a step to the right for tails.
487.
by kens 2y ago
Moreover, putting nuclear weapons in orbit would be a violation of the 1967 Outer Space Treaty. As an aside, Atlas and Titan were capable of reaching orbit, and were used for the Mercury and Gemini missions respectively. Minuteman, on the o
488.
by kens 2y ago
No, you can't remove the random walk error by integrating. The point is that after integrating, what you're left with the random walk error. To make this concrete, if you buy a commercial-grade gyroscope for $10, it will have a ra
489.
by kens 2y ago
I've got the book on my desk right now :-) It's a bit of an unusual book because it is full of technical details but it also has a fair bit of sociological content like "the construction of technical facts", "techno
490.
by kens 2y ago
It depends. For Minuteman I, the missile needed to be physically rotated in the silo to be aligned with the target. Then the "Targeting Van" connected to the missile, downloaded the new targeting data to the disk, and checked that
491.
by kens 2y ago
Well, accuracy makes a big difference if you're trying to hit a hardened target like a missile silo. Missile guidance has been a constant effort to squeeze out more and more accuracy. Minuteman I started with an accuracy of 2 km, but n
492.
by kens 2y ago
I think you're talking about the Titan missiles, which use hypergolic propellants. The Minuteman missiles are solid fuel, so there are no separated chemicals.
493.
by kens 2y ago
Those boards are from the Minuteman I, the cylindrical computer. I wonder what happened to his boards?
494.
by kens 2y ago
I'm always ready with my microscope to take some die photos!
495.
by kens 2y ago
Nice collection of Autonetics photos! Are those your photos?
496.
by kens 2y ago
Thanks! I fixed that.
497.
by kens 2y ago
They did dozens of tests of the Minuteman missiles and reentry vehicles. The warheads were tested underground until the comprehensive test ban treaty of 1996. So it's pretty likely that the systems would work if needed. One risk is tha
498.
by kens 2y ago
I refrained from including that link :-)
499.
by kens 2y ago
In a serial computer, you have a 1-bit ALU, say an full adder that generate a sum and carry. Each clock cycle you read two bits and feed them into the adder, and then you write back the sum. You hold the carry in a flip-flop to use in the n
500.
by kens 2y ago
I planned to write about the electromechanical Torpedo Data Computer used in WWII, but I got distracted.
501.
by kens 2y ago
Sodium chromate is highly corrosive to humans (as well as carcinogenic, see the movie Erin Brockovich). However, it inhibits corrosion in metal, acting as a passivating inhibitor, forming some sort of protective oxide. I've been doing
502.
by kens 2y ago
Author here if anyone has questions...
503.
by kens 2y ago
I'm surprised that the article doesn't mention Fourier transforms and neither do any of the comments. All the talk about aliasing and different filters makes a whole lot more sense if you take a look at the frequency domain. (Unfo
504.
by kens 2y ago
The article states that Intel has 75.9% of datacenter CPU shipments and AMD has 24.1%. This implies that ARM has 0% of the server market, which is not the case. I suspect this article neglected to state the important restriction to "*x
505.
by kens 2y ago
An entertaining article. It's strange to see cadmium described as something obscure that hardly anyone encounters. NiCad batteries were pretty common as well as CdS photo resistors for anyone doing electronics.
506.
Susan Wojcicki, Former YouTube CEO and Influential Google Exec, Dies at 56(variety.com)
2 points by kens 2y ago|1 comments
507.
by kens 2y ago
You might find "The neural network zoo" helpful; it's a chart showing the different types of neural networks, along with a brief discussion of each type: https://www.asimovinstitute.org/neural-network-zoo&#x2F
508.
by kens 2y ago
According to https://en.wikipedia.org/wiki/Criticism_of_the_Space_Shuttle... , the incremental cost was $6,435 per pound and the complete cost was $27,000 per pound. I thought a lot about this, and there are arguments f
509.
by kens 2y ago
The photo with white paper is the Thermal Impulse Printer System, a different printer from the Interim Teleprinter. As far as I can tell, the teleprinter always used yellow paper. (This helps to figure out which printer is being used on the
510.
by kens 2y ago
I think you posted this just as I was removing the <code> tag, so you're looking at the (hopefully) working fonts, not the bad fixed-width font.

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