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Comment Re:Inadequate Buffer (Score 1) 133 133

100 feet of buffer is inadequate. How the hell do you measure your AGL when you're flying? You either use a radar altimeter ($25K installed on an airplane worth $20K) or you use the baro altimeter, which has an acceptable calibration error, plus the local altimeter setting (atmospheric pressure) which has an error band, and there's error because you're not right over the reporting station.

Well, if you had a good GPS receiver and sufficiently detailed topographic maps on board you could also guesstimate AGL that way--but I agree that it's still a dubious and non-robust approach. And your radar altimeter doesn't have to run $25K if it only needs to work up to a few hundred feet and only be "hobbyist" or "drone" rated.

But really, forget measurement--that's probably not even the biggest problem. I suspect that it would be very technically challenging for these craft to physically maintain their permitted altitude. A good gust, an up- or down-draft, and your plus-or-minus 100 feet goes by in no time.

Comment Re:Slashdot summary, as usual, misses the point (Score 1) 115 115

OTOH, my fascist firewall blocks blog posts such as Callaway's, so I really appreciate the hop through an unblocked source. I take it from context that article covers some stuff that isn't in the blog post, as well.

You're thinking of this as an either-or situation, when it really isn't. Hyperlinks are cheap. There's no reason for the summary not to clearly say, e.g."Here is the original blog post in its entirety, and here is an article which discusses some points from the blog post along with some other stuff." If they can't even manage that, then the link should at least clearly indicate that it isn't to the content described in the summary.

Instead, the Slashdot summary fails to link to the original blog post and implies misleadingly that the link in the summary actually does do so.

Comment Slashdot summary, as usual, misses the point (Score 5, Informative) 115 115

If we're going to talk about Callaway's Points of Fail, and create a link in the Slashdot summary that *looks* like it takes you to that list, then perhaps there should actually be a link to the list.

Callaway's original Points of Fail blog post.

You know, instead of the usual Slashdot way of pointing to an article wrapper that talks briefly about some of the points and then eventually links to the real list.

Comment Re:"Pocket dialed"? (Score 2, Interesting) 179 179

It must happen to people a lot

In New York City in 2012, roughly 40% of 911 calls were apparent butt dials. Their category (calls less than 20 seconds long, no response from the caller) probably includes some other inadvertent calls as well, but the majority are probably phone-in-pocket situations.

Just for NYC, that's more than 10 thousand calls per day, and about 4 million 911 calls per year.

Butts.

Comment Re:This problem needs a technical solution (Score 2) 268 268

That DC10 was designed to hit geese without sustaining damage. You think a 1 kg drone is going to do anything?

Er, no. That's just untrue. See the relevant regulations. Depending on the bird size, the engine has to either not explode or catch fire (for large birds), or continue to operate at 75% power for between 5 and 20 minutes (small and medium birds, flocks of smaller birds) before safe shutdown.

"Doesn't explode or require immediate shutdown" isn't the same as not "sustaining damage". And even though the aircraft would likely survive ingesting a drone doesn't mean it would be good to lose a firefighting aircraft for the time it would take to rebuild or replace the damaged engine.

Comment Re:All code ever written wins (Score 2) 27 27

The goal of the Underhanded C contest is to write code that is as readable, clear, innocent and straightforward as possible, and yet it must fail to perform at its apparent function. To be more specific, it should do something subtly evil.

That sounds just like all code ever written, except some code obviously is not clear and readable. (at least before debugging)

Yes, the original poster's specification should have read, "...it should do something subtly evil on purpose ."

Comment Your monthly algorithm tweak brought to you by... (Score 4, Insightful) 115 115

Okay, so we have a benchmark where the bog-standard human being scores 94.9%.

Then in February (that's three months ago), Microsoft reports hitting 95.06%; the first score to edge the humans.

Then in March, Google notches 95.18%.

Now it's May, and Baidu puts up a 95.42%.

Meh. Swinging dicks with big iron are twiddling with their algorithms to squeeze out incremental, marginal improvements on an arbitrary task.

“Our company is now leading the race in computer intelligence,” said Ren Wu, a Baidu scientist working on the project. ... “We have great power in our hands—much greater than our competitors.”

I presume that next month it will be IBM boasting about "leading the race" and being "much greater than their competitors". The month after that it will be Microsoft's turn again. Google will be back on top in August or so...unless, of course, some other benchmark starts getting some press.

Comment Re:satellites (Score 2) 403 403

One should be very wary of the distinction between "run without refueling" and "run without regular maintenance". Even assuming that the reactor's fuel would last, the ancillary equipment associated with the reactor's operation (coolant pumps and such) and electricity generation (steam turbines) certainly wouldn't be expected to operate unattended and unmaintained for months, let alone years.

That said, the fifty-year planned lifespan of the Nimitz-class includes, if I'm not mistaken, a mid-life refuelling and complex overhaul (RCOH). To be fair, the reactor's fuel would likely last longer than the planned 20-25 years if the carrier weren't actively steaming--but I wouldn't trust the other parts to last anywhere near so long.

Comment Re:It was an app on a WORK-Issued Phone! (Score 2, Informative) 776 776

The solution: leave the phone at work when you are off duty.

That would work...except that the employer insisted that she keep the phone with her and powered on at all times. According to the claim, she was on call for client emergencies, even when off the clock.

Comment Re:Not at fault, but was it avoidable? (Score 1) 408 408

... the real question is, "Were the accidents something a human driver could have avoided?"

It's an interesting question. On the other hand, most collisions are something a human driver could have avoided somehow...but didn't.

Sometimes you have to yield right-of-way because it's clear the other driver isn't going to. Do autonomous cars know that?

I would be shocked if they didn't "know" something like it. I can't imagine any car (let alone the entire group of 44 which didn't have a collision) doing a full year of city driving without encountering multiple situations where another driver failed to appropriately yield the right of way.

Comment Re:Small Airports Have Advantages (Score 4, Insightful) 203 203

As a New Yorker, I much prefer LaGuardia, and strongly disagree with calls for its closing.

The point is, I think, that in exchange for an improvement (real or hypothetical) in convenience for a small fraction of total air travellers, there is a substantial and arguably unnecessary burden of cost and inconvenience to the entire system (which is ultimately paid for out of everyone's pockets--and user experiences).

I would love to see these large airports replaced with multiple smaller airports. A larger percentage of the population would have an airport nearby, and average travel times would be reduced significantly.

Well no, it wouldn't. A fully-served point-to-point network with n nodes (cities served) has on the order of n squared links between nodes. The number of passengers desiring each direct link gets to be very small, very quick, meaning infrequent scheduled flights on small, underfilled, costly-per-seat aircraft. So what happens is that airlines adopt (to one extent or another) a hub-and-spoke model. Most direct point-to-point routings are dropped. If I want to fly from East Podunk, NY (POD) to Los Angeles, I can't get a direct flight POD-LAX. Instead, I get a hop to an airline's hub (JFK or ORD or DTW or wherever), and a connection from that hub to LA: POD-JFK-LAX, or POD-DTW-LAX, or POD-ORD-LAX.

If I want to go to a destination served by a smaller airport (let's call it West Lemon, CA: LEM), then I'm taking three flights: spoke to hub, hub to hub, hub to spoke: POD-JFK-LAX-LEM. And each of those flights carries with it the time penalties associated with loading and unloading passengers and cargo, and a risk of delays or cancellations due to weather and other circumstances--plus the plain old waiting for connections, because service to and from the small airports at POD and LEM is infrequent.

Worse still, all those little commuter flights linking the regional airports to the major hubs are going to take up gates and takeoff and landing slots at those busy airports, slowing down the whole system and/or pushing those less-important flights to less-desirable times of day. Taken all together, offering frequent (or even just daily) service to a lot of small airports is going to mean a lot more flights of a lot more smaller aircraft, and/or passengers frequently making multiple connections. It would be expensive per-seat and vulnerable to failures and delays.

Now, La Guardia is an interesting case. Since it's right next to downtown New York, it draws a substantial number of departing or arriving passengers, and enjoys a kind-of-weird pseudo-hub status for historical reasons. Practically speaking, though, it means that there are effectively two hubs (LGA and JFK) or even three (if we count EWR) serving the same area, resulting in needless duplication of services. Routes that could enjoy frequent service with inexpensive (per-seat) full-sized jets get less-full or more-expensive aircraft, or less-frequent services divided between two or three New York destinations. Local New Yorkers enjoy the appearance of convenient, direct flights, at the cost of making the rest of the system a bit worse and a bit more expensive for everyone.

Comment Re:Makes sense (Score 4, Interesting) 152 152

police injury rates are _much_ higher than most work

Welp...sort of. The U.S. BLP recently published their 2013 census of fatal occupational injuries. The overall fatality rate for the workforce was 3.3 fatal injuries for every 100,000 full-time-equivalent workers per year. Management employees averaged 2.4; sales 1.6--no surprises there, really.

For employees in the "protective service occupations" - police, firefighters, correctional services, animal control, security guards, and so forth - the rate was 6.9 fatalities per 100,000 FTE. (I haven't been able to find data broken out by occupation within the category. If someone can find that, that would be great.) So that's what we expect--police, firefighters, and others do have a riskier job than the average, and riskier than the typical office worker. Somewhat surprisingly, the relative risk is only a factor of three or four different when comparing a police officer to, say, an IT manager.

But...there's the rest of the table. "Intallation, maintenance, and repair" occupations? 7.2 fatalities per 100,000. "Construction and extraction"? 12.2. "Transportation and material moving"? 14.9. "Farming, fishing, and forestry"? 23.9.

The real manly men, in real danger on the job, are apparently out there working with tools, building stuff, drilling for oil, driving big rigs, and cutting down trees.

And let's be honest--a lot of the injuries and fatalities sustained by police officers aren't directly attributable to violent suspects. A big chunk of them come from the fact that the typical frontline officer spends a lot of time moving around--in a patrol car, on a motorcycle, on foot, or on a bicycle. Special laws protecting police officers from insults don't actually reduce their likelihood of being in a vehicular accident, or getting clipped by a passing car during a traffic stop, or slipping on an icy sidewalk in the winter. Looking at the last ten years' police fatalities for the United States, the total number of officers killed in motor vehicle incidents (car and motorcycle crashes; hit by car) is 605. The total number of officers fatally shot, strangled, or stabbed is 553. (And I suspect that the proportion who get shot is even lower in Canada.)

Comment Re:Last time one was used? (Score 1) 55 55

even though the shuttle didn't have an equivalent system for many conditions - see challenger

That was true for 1986 NASA, certainly. Post-Challenger there were major changes (extensions) to the list of abort options - including a new bail-out capability - which made the loss of two engines crew-survivable for the entire ascent, and the loss of all three main engines survivable for most of the ascent. (See the Wikipedia article for details.) As it turns out, we have higher expectations 30 years on. Whodathunkit?

Comment Re:Very unlikely to be triggered in the field (Score 1) 250 250

A commercial plane will most probably undergo through several maintenance events and checks during that sort of time frame, where cycling the power is part of the procedure.

It's very reassuring to know that it probably won't happen.

As other posters have noted, 248 days of operation means skipping twenty-plus maintenance and inspection cycles, plus missing one or more engine overhauls. That sucker's going to fall out of the sky due to a hardware problem before the software error gets the chance.

Even in the absence of regular, scheduled, required maintenance, there will be hardware failures due to stuff wearing out, with sufficient frequency to force reboots at less-than-eight-month intervals. Honestly, the FAA is going to ground any airline that was so lax as to get within six months of tripping over this bug.

That's not to say that this bug is a good or acceptable thing, nor that something like it couldn't have much more serious effects. But this particular error is a non-issue from a real-life consequences standpoint.

Comment Don't know about the technology... (Score 3, Insightful) 93 93

I don't know about the technology or the algorithm(s), but the linked article is certainly nonsense.

“You could use the same basic framework to do robust decision making like trying to come up with insulin and glucose monitoring plans [for diabetes patients],” says Neil Burch, a computer scientist at the University of Alberta who helped design a poker-playing AI earlier this year. “You get regular snapshots of glucose levels, and you have to decide how much insulin you should take, and how often.”

Look, I get it. Nobody wants to admit that they're spending their grant money this way because it's fun to get a computer to play Hold 'em. But that's got to be the dumbest justification I've ever read. Human metabolism is complex, but the pancreas doesn't bluff.

"Everything should be made as simple as possible, but not simpler." -- Albert Einstein

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