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Comment: Re:Not surprised (Score 1) 45 45

by Rei (#50015665) Attached to: Uber France Leaders Arrested For Running Illegal Taxi Company

Uber drivers are subsidized by everybody else. Taxi drivers have to pay high insurance rates because the act of driving a long distance every day for a ton of strangers is a job that inherently leads to a much higher statistical rate of payouts. If they're driving as a taxi on regular car insurance, it's you that's paying the bill for their swindle of the insurance system.

Comment: Re:What plan? (Score 1) 83 83

How do you come to that assumption?

By linking to a peer-reviewed paper on the subject?

A nuclear warhead has lots of trouble to even "hit" an asteroid.

Essentially every space mission we have launched for the past several decades has had to navigate with a far more precision than that needed to get close to an asteroid and activate a single trigger event when close by.

Comment: Re:What plan? (Score 3, Interesting) 83 83

We send spacecraft on comparable missions all the time. And it doesn't really take a spectacularly large payload to destroy (yes, destroy) an asteroid a few hundred meters in diameter. 1/2-kilometer-wide Itokawa could be blown into tiny bits which would not recoalesce, via a 0,5-1,0 megatonne nuclear warhead, a typical size in modern nuclear arsenals (in addition, the little pieces would be pushed out of their current orbit).

I know it's a common misconception that "nuking" an asteroid would simply create a few large fragments that would hit Earth with even more devastation, but that's not backed by simulation data. And anyway, even if it didn't blow the asteroid to tiny bits (which simulations say it would) and even if it didn't push the remaining pieces off trajectory (which they say it does), anything that spreads an Earth impact out over a larger period of time is a good thing - it means the higher percentage of the energy that's absorbed high in the atmosphere rather than reaching the surface (less ejecta, lower ocean waves, a broader (weaker) distribution of the heat pulse, etc), the weaker the shockwaves, the weaker the total heat at any given point in time, and the more time for Earth to radiate away any imparted energy or precipitate out any ejecta cloud. If the choice is between 15 Chelyabink-sized impactor (most of which will strike places where they won't even be witnessed) or one Meteor Crater-sized impactor (same total mass), pick the Chelyabinsk ones. 50 10-megatonne meteor crater impactors or one 500-megatonne Upheaval Dome impactor? Pick the former. The asteroid impacts calculator shows the former generating a negligible fireball and 270mph wind burst at 2km distance, while the latter creates the same winds 25km away (156 times the area) and a fireball that even 25km away is 50 times brighter than the sun, hot enough to instantly set most materials on fire.

But that's all irrelevant because, quite simply, simulations show that nuclear weapons do work against asteroids.

What we need is enough detection lead time to be able to launch a nuclear strike a few months before the impact date (to give time for the debris to disperse). There is no need to "land" or "drill" for the warhead. There is no pressure wave; instead, an immense burst of X-rays is absorbed through the outer skin of the asteroid on the side of the explosion, causing it to vaporize (unevenly) from within, especially near the ground zero point, and creating powerful shockwaves throughout its body. In addition to ripping it apart, the vaporized material and higher energy ejecta flies off, predominantly on the side where the explosion was detonated, acting a broad planar thruster.

Comment: Re:200 cycles? (Score 3, Insightful) 119 119

by Rei (#50008581) Attached to: Samsung Nanotech Breakthrough Nearly Doubles Li-Ion Battery Capacity

On the other hand, if they're doubling capacity, then you only need half the number of cycles (it actually even works *better* than that, as li-ion cells prefer shallow charges and discharges rather than deep ones - but yes, fractional charge cycles do add up as fractional charge cycles, not whole cycles). If you have a 200km-range EV and you drive 20 kilometers a day, you're using 10% of a cycle per day. If you have a 400km-range EV and you drive 20 kilometers a day, you're using 5% of a cycle per day.

Comment: Re:well then (Score 5, Insightful) 119 119

by Rei (#50008563) Attached to: Samsung Nanotech Breakthrough Nearly Doubles Li-Ion Battery Capacity

Top commercial li-ion capacities are about 30% more than they were 5 years ago. And today's batteries include some of the "advances" you were reading about 5 years ago.

I'm sorry if technology doesn't move forward at the pace you want. But it does move forward when you're not looking. Remember the size of cell phone batteries back in the day?

Comment: Re:There are ideas. Here's one. (Score 2, Informative) 193 193

by fyngyrz (#50007747) Attached to: WSJ Overstates the Case Of the Testy A.I.

by "some ideas" you mean "some theory".

Yes, of course. What else did you think I meant? It's an idea. It's not a certainty. I'm not sure what your point is. Care to elaborate?

When I say "no idea" I mean literally we have no demonstrable understanding of any one single cognitive function of the brain. Any brain

You might have meant that, but writing "no idea" didn't (and still doesn't) actually say that. The statement was made that we have no ideas. We do, in fact, have ideas.That was the assertion, and that is my answer.

Human brains? We've got nothing.

Human brains are not what are at issue here, but even so, that statement is incorrect. We have made progress at the small scale (see Numenta's work) and there are multiple ideas out there that presently have significant merit. Personally, as someone working in the field and conversant with a lot of what's going on in the technical sense, I have a fairly high level of confidence that we're much closer than the popular narrative would have us believe. Am I right? We will see. :)

Comment: Human visual processing... not so great. (Score 2) 193 193

by fyngyrz (#50007549) Attached to: WSJ Overstates the Case Of the Testy A.I.

Understanding how humans store and recognize images primarily is not a barrier to AI. It's not memory or image recognition that's the hill to climb; The fundamental algorithmic/methodological challenges are thinking, along with conceptual storage, development and manipulation (these things incorporate memory use, but aren't a storage problem per se.) Hardware needs to be able to handle amounts of ram and long term, high speed storage that can serve as a practical basis for the rest as well. Right now, we're getting close, but it'll be a few more years yet before anything really smart can be instantiated. That's even if we were to figure out precisely how to do it right now.

It is possible -- though I consider it doubtful -- that we would implement human style vision neurology in hardware for an AI, but frankly our abilities are so poor compared to what can be accomplished I really don't see why we'd cripple an AI that way. It'd be abusive. "We could have made your visual recall incredibly acute, but... instead you're like us, and really don't have much more than a general idea what was in a scene after you have seen it." [AI nukes silicon valley] (Mods: that's humor. HUMOR.]

Also, check out Numenta's work.

Of course, understanding how humans store and recognize images is (very) important to our understanding of human physiology and disease, and it's wonderful that we're working on it.

Comment: Re: Coral dies all the time (Score 3, Interesting) 92 92

by fyngyrz (#50006001) Attached to: Genetic Rescue Efforts Could Help Coral Shrug Off Warmer Oceans

"Adds heat" is a woefully inadequate simplification of whether or not it's an issue to be concerned with. When temperature goes up, other things change as a result of the relevant phsyics. For instance, the evap/precip cycle accelerates, carrying more warm air and moisture up, and more cool air and moisture down. CO2 in the upper atmosphere reduces radiation by a factor, but more heat up there, more often, increases radiation. More CO2 almost universally implies conditions better for plants. More and healthier plants means more of all sorts of things and less of others.

Dire predictions: Warming moves the zone(s) within which plants and animals flourish north. There's plenty of room to go, a great deal of northern area is frozen wasteland at this point. More CO2 is good for plants. People might have to move. They do that all the tiime. Coastlines may change and infrastructure may need to maintained, adapted, moved or replaced. That happens all the time. Currently estimated timescale for sea level changes: inches per year. Totally yawn-worthy.

In short, the issue is complex beyond any possible "on noes, warming" assessment -- hysteria is entirely uncalled for.

Science is a method. When facing something new, it involves formulating a hypothesis, testing that to validate or disprove it, and then drawing conclusions. We have not seen and do not know what happens when CO2 increases by large amounts due to our production of it. In the historical record, CO2 increases trail warming, not lead it -- which is another way of saying that historically speaking, CO2 increases herald cooling, so that is not any kind of adequate confirmation of the idea that human-caused CO2 increases will lead to significant climactic warming. Doesn't mean it won't -- it just means that this is a new thing and that drawing conclusions either requires flawless modeling that takes everything significant to the process into account (which we don't have... not only in re natural processes, but in re unanticipated technology), or actually seeing what happens. Without one of those - which again, we don't have -- it's not settled science. It is unvalidated hypothesis.

o Yes, we should be trying to figure this out.
o No, we have not figured it out.

When will we know when we have figured this out? When we have a model that accurately predicts climate change as known to have occurred in the historical record.

PS: coral does not "die when you touch it." I have multiple coral reef tanks. I touch my corals (hard ones and soft ones) all the time to move them around, frag (subdivide and transplant) them, brush them when I'm reaching for something else. I cut colonies of soft corals with a razor in order to divide them into more than one instance and place them in multiple places and/or share them with other coral reef owners. Certainly doesn't kill them (doesn't even seem to hurt them.) For hard corals, you break them into separate instances (frag them) with tools that are basically smallish hammers and chisels. You even do this out of the water. Again, doesn't kill them. They don't die because they were bothered or touched. I've never, ever seen that happen. Some of them don't react at all or very much, but the most I've ever seen them do is pull away or retract, dependably to return to their original extension and condition within minutes of the disturbance that caused it ending. Fish touch them all the time as well. Doesn't hurt a thing.

The things that I have seen be directly and immediately detrimental to corals are Ph changes, temperature changes, salinity changes, very large and sudden changes in lighting, and the actions they engage WRT each other (chemical warfare among corals has to be seen to be believed. They are nasty to each other at times.)

Climate change panic bores me. Climate change dismissal bores me. But, like a lot of other induced hysteria, it's a major component of pop culture and the media's slavish devotion to fanning same, so I have to actually work to avoid both. :)

Comment: From TFA: (Score 4, Insightful) 211 211

by Rei (#49993911) Attached to: France Could Offer Asylum To Assange, Snowden

Taubira doesn’t actually have the power to offer asylum herself, however. She said in the interview that such a decision would be up to the French president, prime minister and foreign minister. And Taubira just last week threatened to quit her job unless French President François Hollande implemented her juvenile justice reforms.

So, basically, "not going to happen".

Comment: Re:Little does we know... (Score 1) 167 167

by Rei (#49983939) Attached to: Elon Musk Probably Won't Be the First Martian

Nothing wrong with a piece of fiction with laughably bad science on almost every page. If someone gets a kick out of the book, then it's met its purpose. But when the author gets treated as a "Mars expert" due to his his "hard sci fi" novel, that's where I start having a problem.

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