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Comment Re:200 cycles? (Score 3, Insightful) 132

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) 132

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 3, Informative) 230

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) 230

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) 167

"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) 213

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:The Moon is the way to go (Score 1) 169

Why would you build a moonbase for a radiotelescope or gravity wave detector? What's the argument for dropping it into a gravity well (where it can be exposed to moonquakes and moon dust) and having people operate it when you can just have it unmanned and in space (Earth-Moon L2 for a radiotelescope, Earth-Sun L5 for a gravity wave detector) at orders of magnitude less cost and far greater effectiveness?

Every one of these sort of proposals just screams "I'm an excuse that was made up solely to give us a reason to go back to the moon". The most glaring is surely 3He mining, of course ;)

Comment Re:Part of why I didn't become an astronaut (Score 1) 169

We see the propulsion breakthroughs right now - there's a wide range of propulsion systems possible with current technology. Unfortunately, the turnaround on these sort of things is measured in decades (generally with a number well over "1"). And if it has any form of the word "nuclear" in the title, multiply the average time from conception to deployment by a large number.

Comment Re:dirt cheap rocket launches (Score 1) 169

Nobody of course is requiring rockets to be our long-term future. I have a soft spot for the Loftstrom loop concept, for example (aka, a track that holds itself up via the centrifugal force of a rapidly spinning rotor magnetically suspended in a vacuum inside it). Way more efficient and high throughput than a space elevator and requiring no unobtanium.

Comment Re:dirt cheap rocket launches (Score 1) 169

It would of course not make fuel cheap until we can learn to mine cheaply in space. And we're not even 1% to that stage. You have to pretty much relearn how to do everything you take for granted on Earth in space. Look at Philae just attempting to softly touch down at very low speeds - it had four different ways to try to stop it from bouncing (shock absorbers, ice screws, harpoon, counter-force rocket), and it still bounced way off and ended up in some rocks somewhere. And you're picturing setting up a whole refinery there? Yes, some day. But that day is not close.

The radiation issue is a big one that a lot of people downplay (they forget that the only reason the Apollo astronauts got away with as little shielding as they did was that their missions were on the order of a week or so long - and even still, they would have been in bad shape if a solar storm had hit. As it was they reported seeing regular flashes of light from cosmic rays impacting their retinas.

There've been a number of proposals for how to deal with shielding. One is to build a mini-magnetosphere around the spacecraft; my last reading on the subject was that it would be a realistic way to deflect most solar radiation but not GCR. You still really need physical shielding (which is a complex topic... beta and gamma are blocked by heavy metals far better than they are by light materials, but neutrons need to be moderated down to be stopped effectively, which means light, high scattering cross section elements like hydrogen; heavy ions tend to multiply high energy neutrons. And to make matters worse, forms of radiation switch around - betas kick off gammas due to bremmstrahlung, gammas can kick off photoneutrons or betas, betas can kick off neutrons too, neutron capture kicks off gammas, transmuted elements decay releasing gamma, beta, positrons, alphas, sometimes neutrons... It's really tough.

Most proposals call for using fuel, water, oxygen, etc as part (but not all) of the shielding - it's particularly good against neutrons, as all of these things are generally composed of CHON, all of which are good moderators (especially the hydrogen). A common proposal is to have the heaviest shielding around the beds, as you get better bang for your kilogram that way. I've pondered a more advanced version of that, having significantly more fuel / water / etc tankage space than you need (the extra mass would be part of your shielding anyway, so it's not really a "penalty") and having a computer system intelligently pump it around to where people are at any given point in time and where the sun is / what the current solar radiation flux is / etc. I wouldn't be surprised if you could cut the radiation dose to less than half in that manner, possibly a lot less. You'd need durable, reliable pumps, of course.

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