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Comment Re:Unfortunately no and I have a reason (Score 1) 200

Personally, I don't think he does a great job explaining algorithms .... It is an exhaustive catalog, but it's not a great learning tool.

I agree with all of the above. There are better books. But criticizing TAOCP is like saying the emperor has no clothes. The series is difficult to understand, and everyone thinks it is their own fault for not being smart enough, rather than that the books actually aren't very good.

Disclaimer: I own the entire series, and keep them in my office to impress people, but I haven't actually opened them in the last 20 years.
Additional Disclaimer: I loved Don's "Concrete Mathematics" book ... for the humor as well as the math. I keep it in my office to impress people too.

Comment Re:Not a unique situation (Score 2) 83

I bought a PC a while back which the family stopped using because they forgot their password and couldn't get in and it didn't come with media so they could recover it, obviously they never made recovery media but I'm sure lots of people don't — and of those who do, probably very many of them lose it anyway. I recovered the Admin password and ran the recovery on the hidden partition and bingo, back to factory state.

There's a shitload of people buying PCs for no good reason all the time.

Comment Re:I think the answer is obvious (Score 1) 239

Reliable is more important than cheap.

You need both for uptake. The average person won't spend more than about $300 for a gadget, and they'd rather spend $100. $300 is a pretty feasible price target for a small printer with one extruder. You could sell it without a heated bed at that price, and tell people to print only in PLA. There is high-temp PLA now which can be annealed in an oven and then handle somewhat higher temperatures, so that would cover most people's needs. Do a delta since it is cheaper to make it stable and avoid backlash, and because it uses only four sensors — ideally three hall for the X Y Z_MAX, and an inductive on the Z_MIN for bed leveling. $300 is not even a challenging price point; it can be even cheaper if you skip a display, which I don't actually think is that useful if you're not installing the printer in a remote location.

Comment Re:Stupid (Score 1) 228

Your green option is completely unviable not to mention that it has the same problem that you mentioned yourself, it's similar to petroleum diesel, hello NOx and particulate emissions which are primarily the reason for this ban in the first place.

No. Politics is the reason for this ban in the first place because the NOx is a solved problem with urea injection and the particulate emissions of gasoline are more hazardous and just as prevalent as those from diesel.

Comment Re:How the fuck.... (Score 1) 228

The proliferation of gas at service stations is even higher in Oz than in Europe. I had no problem driving an gas powered Commodore from Perth to Broome, I don't see why trucks would either.
Also the really long haul trucks have much bigger tanks than the traditional ones.

Yes, but for a laden truck the question is whether it's getting high or low single-digit MPGs, so it's still an issue. The energy density of ethanol or propane is arse.

Comment Re:I think the answer is obvious (Score 1) 239

3D printing is still fiddly, complex, error-prone, expensive and slow.

This. We could stop here but let's not, I have more to say as well.

FDM style printers (the cheapest kind) require wrapping your head around calibration, nozzle diameters, temperatures, slices, alignments, supports, bed heating, the properties of PLA / ABS and all the rest. If you're lucky you'll set the printer going and hours later your efforts will yield some crudely finished single colour part. If you're unlucky you'll come back to discover something that has skewed left, warped on its base, or turned into some dante-esque spider's web that has stuck to everything.

#1 thing that should have been done/should be done to improve 3d printer uptake is working automatic bed leveling. AFAICT (and I am about to test this theory) the best way to accomplish this is with an inductive sensor designed for iron, detecting an aluminum print bed. Aluminum is pretty much the best base anyway, since glass can break all to crap while you are removing your print job. Inductive sensors literally cost five bucks and the hardware needed to interface one which isn't already present on e.g. RAMPS literally amounts to a grand total of one voltage divider, aka two resistors. IIRC 10k and 15k are typical, but whatever it takes to get the output signal down to 5v. It doesn't even matter whether you get one which is NO or NC because the software (Marlin, in my case) can detect either type of signal with correct configuration.

The #2 thing that should have been done is more centralized sharing of print temperature settings for materials. After bed leveling, just finding working print settings is the biggest PITA. If you're not buying from someone who gives you some starting values to work with, then you have to go on a web safari quest to figure out where to start.

Way down the list, probably, is eliminating all these stupid microswitches. Hall sensors are more reliable and cost little more. Even if you have to get them on eBay, whole PCBs with a sensor mounted on them are only about twice as expensive as microswitches worth buying.

As for the single-material print job issue, this is the printer I've got, it's reasonably priced and its great sin seems to be a crap auto-leveler. I've got an inductive one in the mail. Deltas take most of the fiddly-ness out of the system at the cost of potentially dropping a hot extruder on your print job if you don't program them correctly. Which all comes back to your point... they should be set up better for the user. I am willing to do all this fooling around to get the thing working but the average user just wants to print and have something come out.

I actually don't think having a crappy-looking single-color print job come out is what keeps most people uninterested in 3d printing at all, though. I think it's really all about the PITA factor. If you offered people a machine which was both cheap and easy to use, they'd jump all over it even if it only had typical resolution and speed and was limited to a couple of materials.

Comment Re:Beginning of the end (Score 3, Informative) 100

This has happened before, when plants first evolved the C4 cycle about 35 million years ago. It wasn't until about 6 million years ago that C4 became ecologically significant, when grasslands became widespread. The resultant fall in atmospheric CO2 caused global cooling and may have been a reason for the ice ages.

Comment Re:Surprising? Not so much. (Score 2) 116

The UK masquerades as a democracy, and has for a long time. In reality it's the most hilariously over the top nanny state

Democracies and nanny states are not mutually exclusive. In fact, they are strongly correlated. Lots of voters want the government to be their mommy.

The problem with the UK is that they lack the checks-and-balances that many other democracies have. The lower house has nearly all the power, and the PM has a majority coalition that can ram through stupid laws very quickly.

Comment Re:Beginning of the end (Score 1) 100

If this technology escapes the lab this would be the ultimate weed

Since it is something that is manufactured, and had no ability to reproduce on its own, that is unlikely. It is no more likely to "escape" than any other solar panel. Do you also worry that motorcycles might escape from garages and start reproducing in the wild?

Comment Re:Billing address? (Score 1) 105

Nobody asks my address at the electronics shop when I have a $800 TV in my cart.

That is a "card present" transaction. If the card is physically swiped or inserted they don't need your address because they can verify the transaction with the data from the mag-stripe or chip.

The fraud discussed in TFA is for online "card not present" transactions.

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