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Comment Re:Nope (Score 2) 170

It certainly steepens your descent profile, but the scenario in question was the plane running out of power while circling. And even a couple minutes worth of propulsion at landing makes a world of difference (2% of a 90 minute flight = nearly 2 minutes).

but if it's not enough to do a go-around, it's just not enough.

Seriously, you're demanding go-around capability on emergency, out-of-"fuel" landings?

Comment Re:Nope (Score 3, Interesting) 170

The funny thing is, electric aircraft can regenerate on descent. If for some strange reason you "ran out of power" in the air, yes, you'd have to make an emergency landing, but it would be an emergency powered landing. Unlike the unpowered landing a combustion-powered aircraft landing has to make if it runs out of fuel.

Comment Re:Are they sure they don't mean (Score 2) 170

Yes, I prefer my airplanes to be filled with nice safe hydrocarbons. They never burn.

EVs have a lower per-km rate of fires than gasoline cars (various figures suggest around 1/5th the rate). Why would it be any different with aircraft? Furthermore, it's much easier to make components redundant with EVs. Electric motors are light, batteries packs are easy to isolate from each other with no extra weight penalty, etc. In one design NASA has been working on there's a huge number of small props on the wing; they're only run at full power at takeoff, but beyond redundancy, they provide a huge amount of extra lift, greatly reducing takeoff distance. So far, though, they've only built a wing testbed ;)

Comment Re:Amazing (Score 3, Insightful) 170

Quite to the contrary, I think it's absurdly pessimistic. People always underestimate S-curves. They did it with wind, they did it with solar, people are in various phases of realizing that they did it with EV passenger vehicles, and they're actively doing it with electric road transport, electric marine transport, and electric aircraft.

There's several companies close to offering electric puddle jumpers. Today. It's not going to take 22 years to transition.

Comment Re:Amazing (Score 4, Interesting) 170

I assume you're kidding. People have been flying electric light aircraft since 1997, when the Alisport Silent Club added an electric takeoff option. The fastest manned electric plane, the 330 LE, goes 340 kph. For the low-end consumer, you can get an Electraflyer-ULS for under $60k. While it has a 2 hour flight time, it's more like a powered glider, of course, with a very low cruising speed. For a bit more ($104k) you can get a 2-seater a Pipistrel Alpha Electro with a cruising speed of 200 kph and a range of 600km.

Submission + - How To Tame The Tech Titans - Google, Facebook, Amazon (economist.com)

dryriver writes: The Economist has published an interesting opinion piece: "Not long ago, being the boss of a big Western tech firm was a dream job. As the billions rolled in, so did the plaudits: Google, Facebook, Amazon and others were making the world a better place. Today these companies are accused of being BAADD—big, anti-competitive, addictive and destructive to democracy. Regulators fine them, politicians grill them and one-time backers warn of their power to cause harm.

Much of this techlash is misguided. The presumption that big businesses must necessarily be wicked is plain wrong. Apple is to be admired as the world’s most valuable listed company for the simple reason that it makes things people want to buy, even while facing fierce competition. Many online services would be worse if their providers were smaller. Evidence for the link between smartphones and unhappiness is weak. Fake news is not only an online phenomenon."

But big tech platforms, particularly Facebook, Google and Amazon, do indeed raise a worry about fair competition. That is partly because they often benefit from legal exemptions. Unlike publishers, Facebook and Google are rarely held responsible for what users do on them; and for years most American buyers on Amazon did not pay sales tax. Nor do the titans simply compete in a market. Increasingly, they are the market itself, providing the infrastructure (or “platforms”) for much of the digital economy. Many of their services appear to be free, but users “pay” for them by giving away their data. Powerful though they already are, their huge stockmarket valuations suggest that investors are counting on them to double or even triple in size in the next decade.

There is thus a justified fear that the tech titans will use their power to protect and extend their dominance, to the detriment of consumers (see article: https://www.economist.com/news...). The tricky task for policymakers is to restrain them without unduly stifling innovation.

Submission + - You May Be Able to Use Google's 2-Step Verification After All! (vortex.com)

Lauren Weinstein writes: Yesterday, I was approached by a long-time reader who told me that he had long been trying — without success — to use 2-factor, had been unable to get assistance from Google in this regard, and wondered if I could help. Perhaps you’ve had the same problem.

This Google user needed to make use of various non-Google applications via his Google account, that seemingly would only function when his Google account had 2-factor disabled.

Comment Re:Same for the moon. (Score 1) 192

That's the whole point of the kilopower project, to make a small reactor with low weight and decent output, with minimal maintenance required. I can't find the projected weight for the eventual product, but they don't look huge in the pictures. Output ranges from 1kW to 10 kW. See https://www.nasa.gov/directora... for specs and more information. They expect to use 4 units for a mission to mars, for a base electric output of 40kW. Their video shows a rocket cutaway with 4 of these packed with other mission gear. I don't think weight is going to be a big issue.

Submission + - Electric Black Hole Jets Are Electric Universe Confirmation

Chris Reeve writes: The previously controversial claim that "astrophysical jets are fundamentally electromagnetic structures" is becoming accepted by some astrophysicists. A summary of recent publications on the subject by Don Scott in particular notes the common presence of counter-rotating cylinders in black hole jets, a feature not expected by conventional models, yet a hallmark feature of Birkeland currents which was mathematically described in a 2015 paper. Counter-rotating cylinders are considered an important prediction for the Electric Universe claim that large-scale electric currents travel through space over plasmas. This recent acknowledgement offers additional vindication for the historical claim that the history of Birkeland Currents appears to be mired in politics. A 2007 Slashdot post titled "Astronomers Again Baffled by Solar Observations" elicited a number of hostile reactions by Slashdot readers that the Electric Universe is obviously a "crackpot theory," but what happens if astrophysicists start to widely acknowledge that large-scale electric currents do indeed flow through space?

Submission + - Chinese Smartphone Manufacturer OnePlus Annouces Credit Card Breach (theverge.com)

sqorbit writes: OnePlus, a manufacturer of an inexpensive smartphone meant to compete with the iPhone, states that data from 40,000 customers credit card information was stolen while purchasing phones. Although only recently announcing the breach OnePlus states the the script stealing information had been running since November. It is not clear whether this was a remote attack or the attack happened from within the company. Credit purchases on the OnePlus site have been suspended and will remain that way while an investigation takes place.

Submission + - New Blood Test That Screens For Presence Of Cancer Already 70% Effective (bbc.com)

dryriver writes: Scientists have taken a step towards one of the biggest goals in medicine — a universal blood test for cancer. A team at Johns Hopkins University has trialled a method that detects eight common forms of the disease. Their vision is an annual test designed to catch cancer early and save lives. UK experts said it was "enormously exciting". However, one said more work was needed to assess the test's effectiveness at detecting early-stage cancers. Tumours release tiny traces of their mutated DNA and proteins they make into the bloodstream. The CancerSEEK test looks for mutations in 16 genes that regularly arise in cancer and eight proteins that are often released. It was trialled on 1,005 patients with cancers in the ovary, liver, stomach, pancreas, oesophagus, colon, lung or breast that had not yet spread to other tissues. Overall, the test found 70% of the cancers. In some cases, the test also provided information about the tissue-of-origin of the cancer — a feat that has been difficult in past. Dr Cristian Tomasetti, from Johns Hopkins University School of Medicine, told the BBC: "This field of early detection is critical. "I think this can have an enormous impact on cancer mortality." The earlier a cancer is found, the greater the chance of being able to treat it. Five of the eight cancers investigated have no screening programmes for early detection. Pancreatic cancer has so few symptoms and is detected so late that four in five patients die in the year they are diagnosed. Finding tumours when they could still be surgically removed would be "a night and day difference" for survival, said Dr Tomasetti.

Comment Re:Uhm... No? (Score 3, Insightful) 97

It's not as interesting as what I though it was going to be about. I'd like to see a series of a dozen or two small, high-temperature-capable reaction vessels (some glass, some platinum-coated steel), each with its own temperature and pressure regulation hardware, and self-reconfiguring plumbing fixtures attached to it (gas/liquid multiplexers). Some vessels would come with common catalyst packs in them (platinum, vanadium oxide, iron, etc), some capable of maintaining a temperature gradient for distillation, some for gas-liquid exchange, some with stirring hardware or an auger to remove precipitates, one with electrodes for electrolysis, etc. A couple heat exchangers also would be nice (potentially the same hardware as the MUXes), as well as a the obligate pump(s) and compressor(s). And of course you need hoppers for solid feedstocks, feed lines for liquids and gases, etc. A nice touch would be if one or more XYZ-axis arms could move between different feedstocks and/or containers for finished products.

Something like that, where the vessels remain constant but the lines between them reconfigure based on software inputs, would be amazing. Doesn't need to be large - even a desk-sized unit would be very useful. And such a thing would be invaluable for space applications, too; it's one thing to set up offworld production of certain largescale feedstocks, but a whole different thing to try to set up production of every chemical we use as a society, and in particular those needed to keep your industrial processes going. Small-scale batch synthesis is an option, but that requires human labour, and humans leave a massive trail of required consumables in their wake. Automated lab synthesis, however...

But as for this? I don't see the point of the 3d printer. They're just printing a bunch of simply interconnected vessels and then manually doing a series of reactions in them.

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