In the 2016 #USA election, #Trump might have won the popular vote too if people had thought their votes mattered.
How to ask good technical questions, by Julia Evans
Malte Skarupke describes his ska_sort, a radix #sorting algorithm that beats the comparison-based implementation in (some implementation of) the STL on modern hardware by a factor of two to seven, largely due to better instruction-level parallelism. Typically it starts to win at about 64 items. #algorithms
A BIOS-based boot sector hello-world program (not really a bootloader)
DigiNotar, SSL/TLS, Iran intercepting Gmail (and foiled by certificate pinning), #security
suggested avenues for learning about #deep-learning, including recommendations of software, etc.
Ian Goodfellow’s #ebook on #deep-learning #neural-networks; supposedly the most comprehensive available. Goodfellow is the guy who invented GANs I think. #machine-learning
overview of #soil #moisture #sensing #hardware, including oven-drying; neutron thermalization sensing; gamma-ray attenuation sensing; and electromagnetic sensing (of resistivity or polarization), including measuring via a porous block; tensiometers; microwave thermal emission sensors; NMR sensors; simple thermal sensing; time-domain reflectometry; hygrometric techniques using air in equilibrium with the soil; electrolysis current measurement; and optical methods. By Nicole Huggins-Rawlins.
a 1987 patent for microwave #moisture #sensing #hardware using attenuation of microwaves by moisture.
Another patent on microwave #moisture #sensing #hardware, this one from 1984, this one using microwave reflectivity of a sheet of possibly moist paper.
Another microwave #moisture #sensing #hardware patent, this one from 1986, again for measuring moisture in paper.
a 2012 article about #sensing #hardware using microwaves to measure paper #moisture, explaining how they measure the resonant frequency of a resonator built around a capacitance (I guess?) that depends on the moisture content of the paper.
The same dude who wrote the microwave #moisture #sensing #hardware article about paper wrote this other one about mozzarella; says accuracy is about 0.5%.
This industrial #moisture #sensing #hardware using microwaves to measure stuff on an production line supposedly has ±2% accuracy over a 1% to 85% range; it’s intended for wood products and chips.
ASTM’s D-2974 standard for #moisture #sensing of #soil, plus other soil analysis. They specify oven-drying and burning, which I guess makes sense if you want the most precise values.
#ceramics clay has water content between 19.5% and 22.5%, but the difference between soft and stiff clay is only about 1% #moisture, because solutes influence flocculation.
7-page #pdf on #ceramics clay bodies, including A.R.T. Studio Clay Company’s catalog of clays.
Hey, there’s a #ceramics subreddit.
how to centrifuge #soil to analyze it into parts, using sodium hexametaphosphate and an ultrasonic probe to disperse it in water. Separates silt from clay.
#Soil centrifuging method #pdf, using sodium hexametaphosphate and an ultrasonic probe, suggesting 750 rpm.
#PDF on separating different clay #materials from the 1960s.
#ceramics recipes and tips
how to join clay for #ceramics, with slip or blending.
Mitsubishi’s 1994 metal clay patent for sintered precious metal #materials: 50% to 90% precious metal (in particles of under 200μm), 0.8% to 8% water-soluble cellulose binder (methylcellulose or ethylcellulose), 0.08% to 3% surfactant (soap; recommended polysoap or alkyl benzene sodium sulfonate), 0.1% to 3% oil, remainder water. Also mentions boiled rice or wheat flour as previous binders, but says the cellulose burns off and discolors the metal less. The oil is to keep it from sticking to your hands; suggests di-n-butyl phthalate, PEG, PVA, etc. Also says ethylene glycol enhances moldability. The cellulose gels during heating. I bet you could use this binder for non-clay #ceramics like zirconia and alumina, too; and I bet other water-soluble polysaccharides like mucilage would work.
a #paper on how plasticity of #ceramics clay #materials changes with #moisture, explaining Atterberg limits and whatnot
explanation of grog, with photos of some spectacularly grog-tempered pots. #ceramics #materials
Different clay tempers for #ceramics; notes that paperclay smells terrible during firing
#spaced-practice on Wikipedia (like Anki, AnyMemo, SuperMemo)
#pdf #paper from 1978 showing a strong #spaced-practice effect on postmen learning to type on typewriters: 60 hours of practice spread over 12 weeks was more effective than 80 hours of practice over 3 weeks. There was even a significant improvement (about 15% on learning efficiency) from doing two one-hour sessions per day instead of one two-hour session. This shows that spaced practice isn’t just for memorization. By Baddeley & Longman. #psychology
the #paper introducing generational #garbage-collection; Lieberman & Hewitt 1980, but not published by ACM until 1983. I think this version wasn’t practical but I don’t quite remember why.
How FAT works. #filesystems
Another, shorter explanation of FAT #filesystems.
Getting a “hello, world” to boot under UEFI under QEMU.
How CP/M #filesystems worked. It was not remotely FAT-compatible.
#pdf by Learning Pool’s Donald Clark about #education #psychology and in particular #spaced-practice. Fairly illiterate, but mentions some interesting points.
#pdf whitepaper promoting some company’s vaguely described wares that claims that #education #psychology shows that “productive struggle” is needed to achieve “deep conceptual understanding and procedural fluency”.
position of the National Council of Teachers of Mathematics on "procedural fluency". #education #psychology
55-page #PDF #paper on #education #psychology evaluating ten learning techniques, half of which are widely used but don’t work. #Spaced-practice is one of the two that works very well, the other being “practice testing”. By Dunlosky et al.
#PDF of Sobalvarro’s 1988 bachelor’s thesis on adding generational #garbage-collection to Lucid Common Lisp in 1986 and 1987 without support from the virtual memory system. He mentions that the Lieberman & Hewitt paper described an approach that required “invisible pointers”. Apparently at this point three other generational GCs existed: Ungar’s in Berkeley Smalltalk, Wirfs-Brock’s in Tektronix’s Smalltalk, and Moon’s on the Symbolics 3600. 68 pp.
#PDF of Scott Aaronson’s new 116-page survey #paper on P=NP. #complexity