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Comment Re:Chameleon-Like Behavior? (Score 1) 191

One of the properties of subatomic particles is referred to as colour. The particles are not coloured (they are far smaller than the wavelengths of light that give colour), but it is a simple system of classifying particles, similar to resistor colour codes or the "terrorist" alert system.

The study of the colour properties is called "chromodynamics", and I guess "chameleon" must be a similar extension of the metaphor.

Comment Re:Die? (Score 1) 229

Your NAND SSD is going to fail during an erase-program (aka "write") cycle, and except in the extremely unlikely case that the pattern you were writing did not involve changing any previously stored 1s to 0s on stuck bits, then the result is going to be wrong. You could read it, but you'd be reading the wrong data.

I disagree. Flash memory erases whole blocks in one go (with a high-voltage pulse). It should be simple enough to check that the whole block got properly erased during the erase part of the write cycle. If not, that is a worn-out sector, and can be marked as such with no loss of data.

Getting stuck in the programmed state is a good thing, it makes the check easier (check for all zeroed before writing instead of checking for a correct write afterwards) and possibly faster.

Correcting some other inaccuracies I noticed during this discussion, flash memory is a specific type of EEPROM (electrically erasable programmable read-only memory). The main failure mode occurs because charge builds up in the gate oxide (the insulator between the floating gate and the substrate).

Comment Re:Not Holding My Breath (Score 1) 120

They did it using an atomic force microscope (very sharp needle) to make room for the phosphorus atoms on the silicon surface (removing the hydrogen termination in certain places). Phosphene gas PH_3 then places phosphorus atoms in the vacated holes, and finally silicon is grown over the top using a low-temperature CVD process. It's a beautiful technique that took them several years to get right.

Comment Bit-flipping (Score 1) 283

Here's an interesting thing: older computer chips are more susceptible to bit-flipping by cosmic rays, because they are thicker. The increased thickness gives the cosmic ray more chance of interacting with the chip (rather than passing straight through), scattering charge all over the place, and stuffing things up. IBM had a serious modelling project in the 80s that culminated in SRIM (free download), but apparently it's not much of a problem for modern computer chips. SRIM has since gone on to bigger and better things.

Comment Re:Institutional Traders Don't Enter Trades Like T (Score 1) 643

I did work experience at a large broker once, and spent a day watching the actual traders (there were only two, even for that large company, on text-based terminals). They say that quite regularly traders at other firms enter the price wrong, e.g. leaving the zero off the end of the price of a large sell order, which eats through all the buy orders and reduces the price quite significantly... they said that most of the traders were pretty good about reversing such transactions.

So things something like the OP describes can and do happen.

Comment Re:Gyroscopic effect? (Score 1) 197

If the flywheel is horizontal, it will strongly resist roll (where a car's weight moves to the outer wheels on a corner), and may improve handling significantly.

If the flywheel is vertical (very unlikely), the car will resist turning and have very poor handling.

Conservation of angular momentum is the same force that makes bikes easy to balance (slow to fall over) when they're moving.

With a spinning wheel, rotating the axis (axle) towards the plane of the wheel is hard, but rotating around the axis offers no resistance.

More reading.

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